The invention relates to a control or regulation of a multipiston squeeze head or block squeeze head of a molding machine for clay-bonded molding material (e. g. molding sand).
In an active pressing process from above with a squeeze head, e. g. consisting of multislides or multipistons, the displacement of individual multislides or multipistons has so far been detected through main control switches (approach switches) or through inductive stroke transducer. Thus, reached positions are registered and processed in a control means. This kind of position measurement is also possible for the squeeze head--with or without multislides or multipistons--as a whole. At present, two prior art documents are known.sup.1.
Compacting of sand by individually operated pistons by oil flow is disclosed in J-A 57/142743 (Komatsu), "Patent Abstracts of Japan," Vol. 006, No. 246 (M176), Dec. 4, 1992. The control of the filling height of sand in compacting units is subject matter of DE-A 41 12 466 (Georg Fischer), as there are used two switch members to physically detect the filling height of the compacted sand.